From the air, the so-called Emerald Triangle looks disconcertingly yellow. Such is the view as pilot Mark Harris tilts his 1957 Cessna 182 at a dizzying angle to get a better view of the rolling California landscape stretching below him.

Harris, an Arcata attorney, often uses his single-prop plane to hop from one county courthouse to the next. But today he’s getting a bird’s eye view of the marijuana farms that dot the forested hills around Upper Redwood Creek in Humboldt County, an area that’s part of the three-county Emerald Triangle region known far and wide for the quantity and quality of its marijuana.

The farms are easy to spot: In clearing after clearing among the trees, dozens of dark green spots, each representing a marijuana plant that’s nearly ready to be harvested, are arranged in tidy rows. But the flight also highlights in stark terms the ecological consequences of such endeavors. The rolling hills in all directions are dusty and parched. And at the base of the hills, curving this way and that, flows the Upper Redwood Creek — or what is left of it. Thin ribbons of water meander past silt-clogged riverbanks, a far cry from the healthy waterway that once flowed through the area.